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The Trees of Great Britain and Ireland

ÆSCULUS OCTANDRA, Sweet Buckeye

Æsculus octandra, Marshall, Arbust. Am. 4 (1785); Sargent, Silva N. America, ii. 59, tt. 69, 70 (1892), and Man. Trees N. America, 646 (1905).
Æsculus lutea, Wangenheim, Schrift. Gesell. Nat. Fr. Berlin, viii. 133, t. 6 (1788).
Æsculus flava, Aiton, Hort. Kew, i. 403 (1789).
Æsculus neglecta, Lindley, Bot. Reg. xii. t. 1009 (1826).
Pavia flava, Moench, Method. 66 (1794); Loudon, Arb. et Frut. Brit. i. 471 (1838).

A tree attaining in America 90 feet inheight and 9 feet in girth of stem. Bark of trunk ¾ inch thick, dark brown, slightly fissured, separating on the surface into thin small scales. Leaves with long slender petioles. Leaflets five, occasionally seven, elliptical or obovate-oblong, cuneate at the base, acuminate, finely serrate, pubescent beneath; petiolules short. Terminal leaflet with twenty or more pairs of nerves. Flowers in pubescent panicles, 4 to 6 inches long; calyx campanulate; petals four, yellow, coming into contact at the tips, very unequal, the upper pair much longer than the lateral pair, claws villose within and much exceeding the calyx, limb of lateral pair obovate or round with a subcordate base, limb of upper pair spathulate, minute. Stamens usually seven, shorter than the petals, villose. Ovary pubescent. Fruit 2 to 3 inches long, brown, smooth or slightly pitted.

Identification

In summer distinguished from Æsculus glabra by the leaflets being pubescent beneath and devoid of cilia in the serrations; from Æsculus Pavia, by the larger leaves, which have petioles with smooth ridges on their upper surface. In winter the twigs show the following characters:—Branchlets glabrous, shining, with a few scattered lenticels. Leaf-scars flat on the twigs (there being no cushion), obovate, with usually three groups of bundle-dots; opposite scars joined by a linear ridge. Pith large, circular, green or white. Buds not viscid, terminal much larger than the lateral, the latter arising at an angle of 45°, long-oval, pointed at the apex; scales brown, the cilia on the exposed margins minute or absent, upper scales rounded at the apex and on the back, lower pair pointed at the apex and keeled on the back.

Varieties

1. Var. hybrida, Sargent (Var. purpurascens, A. Gray; Æsculus discolor,[1] Pursh). This is a form occurring wild in the Alleghany mountains. The flowers are purple or red in colour, and the under surfaces of the leaves, as well as the petioles and panicles, are clothed with a dense pale pubescence.

2. Æsculus versicolor, Dippel. This is a hybrid between Æsculus octandra and Æsculus Pavia, and is intermediate in character, the flowers varying in

  1. Figured in Bot. Reg. iv. 310 (1818).